Beginning with a prologue in which a young Indiana Jones is introduced, the epic continues with the adult Indy embarking on a perilous quest for his father, Professor Henry Jones, Sr. The Nazis are on the trail of the Holy Grail, and have kidnapped the professor, who is an authority on the Cup of Christ. Indy inches through rat-filled catacombs, battles Nazis in biplane dogfights, and braves the firepower of unstoppable tanks.